Piston and piston ring



H. B. JOHNSTON.

PISTON AND PISTON RING APPLICATION FILED DEC. 5. 1919 6 Aug Patente FIG.T.

iimrsn 'ra HARRY B. JOHNSTON, OF SEATTLE, WASHINGTON.

rrs'ron Ann risron RING.

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Specification of Letters Patent.

Patented Aug, 1, H9220 {application filed December 5, 1919. Serial No.342,823.

T 0 all whom it may concern:

Be it known that LHARRY B. JoHNsToN, a citizen'of the United States ofAmerica, residing at Seattle, in the county of King and State of\Vashington, have invented certain new and useful Improvements in,

sealing contact with the walls of'the cylinder to retain the maximumworking pressure of the steam, explosion, gas mixture or other poweragent.

The invention consists in the novel construction of a piston, thering-grooves there in, and packinga'ings fitted to said grooves arrangedand adapted to receive the direct expansion or impulsive forces withinthe power cylinder and in combination with inclined opposing surfacesupon the ringgrooves and rings, respectively, whereby said force tendsto expand said ring, to force the sameagainst the cylinder wall.

In the accompanying drawings,

Figure 1 is a view partly in vertical section and partly in elevation,of a power cylinder, piston and rings therefor, embodying my invention,

Figure 2 is a top plan view of one of the piston packing-rings of myinvent-ion partly broken away,

Figure 3 is a view in elevation, partly in section of one of said rings,on line IIIIII of Fig. 2.

Referring to said views, the reference numeral 1 designates the sidewalls, 2 the top wall of an internal combustion engine cylinder and 3the power chamber therein. 5 indicates a piston reciprocallyoperative insaid cylinder formed with a groove in its upper portion communicatingimmediately withsaid chamber. The top or dome of said piston may beformed with a plain surface 6, as shown.

Said groove comprises a substantially vertical wall 7 at the tip thereofextendin downwardly from said piston-top 6 for so iicient distance toafford space for considerable material in the upper portion of thecontained packing-ring; thence a wall 8 vided forming the upper wall ofan annular projection 10 which terminates at its outer edge in avertical wall 11. An inversely directed inclined wall 12 ofsubstantially the same degree of inclination as said wall 8 forms thelower surface of said projection which intersects with a substantiallyvertical wall 13 of a lower channel 15 of less recession or depth thanthe wall 7 and terminates at its lowermost extremity in an outwardly anddownwardly directed wall 16 of approximately the same degree ofinclination as said wall 8.

A packing-ring 17 is arranged and-adapt ed to be operatively secured insaid groove and conslsts in an upper horizontal face 18 I inclinedoutwardly and downwardly is pronormally in substantially the same planeas the topsurface 6 of the piston, a vertical face 19 opposing thevertical wall 7 of the groove, an inclined face 20 opposing andcorresponding tothe wall 8, a vertical face 21 arranged opposite to thewall 11, an inwardly and downwardly inclinedface 22 opposing wall 12 ofthe groove, vertical face 23 arranged opposite the bottom wall 13 of thechannel 15, and an inclined face .24 of approximately correspondinginclination to said wall 16 of the groove. A vertical outer face 25 isarranged and adapted to bear upon the wall 1 of'thecylinder.

- The-ring 17 is preferably cut, as at 26, on adiagonal line as viewedin end elevation, or in any suitable manner. As designed and assembled,clearance spaces are provided, between faces 19, 21, 23, and 25 of thering and the respective opposing walls of the groove to affordopportunity for unavoidable deposit of carbon and to admit of thelimited movement contemplated in the operative functions of the ring.

In operation, the explosive charge of gas within the chamber 3 actsdirectly upon the top of the piston and partially upon the top face 18of the ring which causes the ring to bear and react upon the inclinedwall 8 urging the ring outwardly and expansively upon the cylinder wall1 and the passage. of the power-fluid is'sealed thereby from escapeabout thepiston by contact between the face 25 of the piston and thewall 1 of the cylinder and by the union between the wall 8 of the grooveand the face 20 of the ring.

In the opposite or upward stroke of the piston when the compressionbelow the pis ton may cause the leakage of cylinder oil past thepistonand into the combustion chamber, the reaction forces between theinversely inclined wall 12 and the face 22 will prevent the passage ofoil thereby and tend to maintain the slidable contact of the outer face25 and the cylinder wall.

The invention is simple in construction, and is positive anduniform inits operation, and the rings are extraordinarily durable in use as whilereceiving a portion of the direct power of. the explosion or expansiongases, they are designed of somewhat larger dimensions and are notsubject to the recurrent expansion and contraction. of the common typeof ring but as they are substantially maintained in operative contactwith the cylinder wall by positive pressure, they are relieved from manyof the effects due to rapid alternations of tension.

What is claimed as new is:

1. In combination, a piston having a ring groove formed at theintersection of the upper surface and side wall of the piston, aninclined wall in said groove extending outwardly and away from theworking face of the piston, a ring mounted in the groove and havin aninclined face corresponding to the incline wall of the piston groove,coacting means 'etween the walls of thegroove and ring to hold the ringin the groove, said ring having an outer face exposed to the workingpressure of the cylinder and lying wholly substantially in a plane andextending from the edge of the groove tov the wall of the cylinderwherebythe action of the pressure on the whole outer surface of theringwill exert a force substantially parallel to the line of travel of thepiston.

2. The combination of a power cylinder, of a pistonhavin a ring-grooveformed at the intersection of the upper surface and side wall of thepiston, an annular projection in said groove having oppositely inclinedwalls on its upper and under sides, and a piston ring mounted in saidgroove having its upper face forming a portion of the upper workingsurface of the piston, and formed with inclined faces opposing,respectively, the said inclined walls of the groove. 4

3. In combination a piston having a portion cut away at the junction ofthe working face and the cylindrical wall thereof, an annular ribextending from the face of said cut away portion between the edgesthereof and having an inclined wall, a piston ring having a groove toreceive the annular rib,-

the groove having an inclined face which cooperates with the inclinedwall of the groove to expand the ring when pressure is applied to thetop of the ring.

4. In combination, a piston having a portion cut away at the junction ofthe working surface and the side wall thereof, a pisi ,eaeaoa ton ringfor said cut away portion having an annular surface adjacent the workingsurface of the piston and forming a substantial continuation thereof andinterlocking means between the piston and ring includ-- ing an inclinedsurface on the piston and a similar surface on the ring" cooperatingtherewith, the surfaces being'in contact at a point substantially inline with the middle of the annular upper surface of the ring.

5. In combination, a piston having a portion cut away at the junction ofthe working face and the side wall thereof, a piston ring for said cutaway portion, interlocking means between the piston and ring includinganinclined surface on the piston and a cooperating inclined surface on thering, the cooperating surfaces being in contact at a point substantiallyopposite the middle of the cylindrical surface ofthering.

6. In combination, a piston havingeai por tion cut away at the junctionof the working surface and the side wall thereof, a piston pointsubstantially in line with the middle of the annular upper surface ofthe ring and substantially opposite the middle of the cylindricalsurface thereof.

7. In combination, a piston having a portion cut away at the junction ofthe working surface and the sidewall thereof, a piston ring for the cutaway portion, and interlocking means between the piston and ring wherebypressure at the end of the piston will expand thering, said meanscomprising two oppositely inclined surfaces on the piston and twooppositely inclined and cooperating' surfaces on the ring.

8. In combination, a piston having a portion cut away at the junction ofthe working surface and the side wall thereof to form a groove, thegroove having two oppositely inclined surfaces, a ring in the groove forcooperation therewith, the ring having two opposite directions relativeto a plane perpendicular t0 the axis of the piston.

In testimony whereof I affix my signature.

HARRY B. JOHNSTON.

